Machine for proof testing the holding efficiency between wire cables and fittings, etc.



Nov. 28, 1944. o. J. BRATZ ET AL 2,363,938

MACHINE FOR PROOF TESTING THE HOLDING EFFICIENCY BETWEEN WIRE CABLES AND FITTINGS, ETC

Filed July 25, 1942 3 Sheets-Sheet l {WWW-MIT al 32 df Je 25 95 F/ 33 770/ l I HMP/Pr.3614055l mm) ATTORNEY Nov. `28, 1944. o. .1 BRATZ ETAL MACHINE FOR PROOF TESTING THE HOLDING EFFICIENCY BETWEENWIRE CABLES AND FITTINGS, ETC

5 Sheets-Sheet 2 Filed July 23, 1942 INVENTORS 0770 JT frz BY f1/PRY ALMsS VAVroRNEY NOV. 28, 1944. Q J, BRATZ ET AL 2,363.938

MACHINE FOR PROOF TESTING THE HOLDING EFFICIENCY BETWEEN wIEE CABLES AND FITTINGS, ETO

Filed July 23, 1942 3 Sheets-Sheet 3 BY HARRY D. SAM/5S Patented Nov.` 28, 1944 t e l UNITED STATES PATE NT OFFICE Application Juiy 23, 1942se`ria1Ne. 452.119' iacieime. 3(01. 7.3-16'0) This `invention relates to a` proof testing machine `fortesting cables and the holding power between end fittings and cables. l

Among the objects of this invention is the production of a machine for testing the strength of e '.cables and for testing `:forsuiiliciency of holding` l power between end fittings` and cables by `placing a ,predetermined load on the cable for a .prede- "termined lengthsoftime. I

Another object of this invention is the'provi` sion of means facilitating adaptation of the ma- .chinefor `testing. cable assemblies of `diierent `lengthsyand different diameters i and equipped `with different end mined loads.

Otherobjects of this invention will appear from `the -following description `taken in connection `with the drawings in which l l Fig. 1 is a top planview `of a testing machine built in accordance with our invention showing parts in horizontal section;

t l' Fig.. 2 is a side elevational fview ofthe machine,

showing partsjin vertical section;` l Fig.` 3 is an enlarged View of the left-hand of Fig.` 2;

. Fig. 4 is end fittings, for different predeter-` a vertical cross section on the line e Fig. 5 is a perspective view of one `ofthe deltachable spring loaded units; y`andL e Fig. 6 is a Wiring "diagram ofja preferred wir- N ving system employed in ycontrolling 'the machine.

For the purposes of disclosure we have `ill`us A.vided Aby a motor which is key and automatically controlled. e .The frame of the machine comprises a long lH shapedbeam `Ill of a` length slightly longer `man theiongest cable mbe tested. `This.teamf* is preferably supported` off the oor `at acon- `venient working height by legs I I preferablysuittrated what now appears to be` a preferredembodiment of our invention in which the motive 'force for placing the cable under tension -is pro- I f.

`ably bolted `thereto and to the oor as indicated.

Inlong frames the H 4beam I0 is made in sec-` tions `asis understood. e x Mountedat oneendlof the H beam IILFigs. l 'and 2,` is a cylindrical thrust receiving housing 3|33securedonthe Hubeam by angle pieces I4 as indicated. Rotatably mounted Within the thrust lolockis threadedly secured on a rod 49 `slidably receiving housing an interiorly threaded cylindrical member I5 heldiand rotatably supported within thehousingby `thrust'-lzxearings :as indicated.- Mountedorr oneend of the member vI5 is e a sprocket wheel It` which is driven at a suitable reduced speed `bva sprocket chain I'I `from` a `motor I8.` H Threadedly engaging the interiorly threaded` member I5 is athreaded pull rodZ which is pro- -vided `with a slidebar coupling block or head` 2I slidable on the Web122 ofthe 'H beam. This block may be held onthe `web by meansofguiding ilanges 23 on rthe upper `portions of the legs ot` the H beam andmay be provided with a wearing plete 24 ending en the web z2.` y

Mounted on the web 22 ofthe `H beam I0'is a sectional composite slidebar 25 provided with wearing plates 2'6"as`ndic'ated'.` Thisbar is pro- .videdq at one `endfwithta hea-d1 21 `for engagement `with a corresponding opening 28 inA the coupling block 2|'. Guides29 secured tothe iWeb 22 are provided toguidelthe movement of the slide bar25.1 l f The slide. berpz-sisprevided with e eeriesyer e spaced threaded holes 3U for` engagementby bolts 3 Iwhichmay be `passed throughdifferent closely spaced holes 32 in a motor pulling block 33 prof vided with an openingor seat35 at one end for receiving: a`tting-36 onone end of a cable 31er for receiving adapters (not disclosed) to receive fittings'of variousshapes and` forms and sizes. By vmeans of this construction the motor pulling block 33 may "be `adjusted on the composite bar 25ior testing differentlengths of cables.

`Detachably` mounted on theother end of the H bearnpIU is a springloaded ypulling block` assembly'fd Fig. 5fwhich` includesY a' 'baseiplate il slidably'f and detachably 'received in` grooves in the side walls of a generally U-shaped pocket" Figs; l and 3 `-which-includes'a cross-webA abutment plate'l44 and' which isssecured as'` by angle irons to the endrof the H beam I0.

*Thepulling block assemblylIU includes a pulll ing block llprovided'with an "opening 4I for;v re- `ceiving the other endfiitting 48 on the cableor fitting adapters (not disclosed). This` pulling l mounted in the base plate 4I and -surroundedby a-helical spring llfseatedeat one end against the base plate 4I and` at its (other end againstga disc 5| surrounding the rod 49 and held in position on the rod by means of nuts 52 by means of which the amount of compression of thle spring may be regulated. A threaded collar 53 is locked to the rod 49 and constitutes a fixed adjusted limiting abutment for the base plate 4|.

Adjustably mounted on the pulling block 46 are plates 54 Fig. 1 which may as disclosed be locked in adjusted position by set screws. These plates carry a switch housing 55 in which are housed two switches which may be of the clicker type. The position of the housing may be adjusted by a screw 56. One of these switches 51 is closed,

Fig. 6, when the parts of the machine are in home position and its function as will be described will be to open the circuit of the motor |8 after loaded pulling block 46 is in its home positionl and is adapted to be closed after a predetermined amount of forward travel of the pulling block 46 and slightly before the switch 51 opens, to set a timing mechanism in operation which reverses the moto-r I8. These switches include plungers which after a predetermined outward movement respectively open and close the circuits'y and which bear against the base plate 4l of the spring loaded pulling block assembly 48.

The controlling mechanism also includes a forward limit switch 60 and a reverse limit switch 6| which are mounted on a plate 62 suitably suspendedfrom the web 22 of the H beam IIJ. These switches are operated by a lever 64 which is actuated by a rod 65 slidably passing through a lug 66 on the slide bar 25. Adjustably secured on the rod on opposite sides of the lug 66 are collars 61 by means of which the rod 65 is operated at the ends of the forward and rearward movements of the slide bar 25.

with Xed collars 68. n

The wiring diagram A suitable wiring diagram for the machine is disclosedin Fig. 6. The motor there disclosed is a three phase motor and the lines from thecurrent supply are indicated by L2, L3 and L| and the lines to the motor by T3, T2 and TI. An op- The other4 The rod is also equipped l erating keyboard is provided with three keys, a

in a forward direction. 'Ihe circuit for the operating coil may be traced from the line L3 across the coil 13, the forward depressed key 10, the reverse key 1| the clicker switch 51, the forward safety limit switch 60, and the stop key 12 to the line Ll.

The forward operating coil 13 is held operated by a locking circuit from the line L3 across the coil 13, one of the contact plates of the contact bar 14, the reverse key 1I and thence across the switches 51 and 68 and the ,stop key 12 to the line LI so that the forward key 1|] may be immediately released.

The motor `.I8 now operates forwardly to pull the motor pulling block 33 toward the right and through the cable pulling the spring loaded pulling block 46 toward the right carrying the clicker switches 51 and 58 away from the base plate 4| of the spring loaded pulling block assembly 40. After the spring loaded pulling block 46 has been moved forward a predetermined distance which in the machine constructed is the plunger of the switch 58 will have moved far l enough to close the circuit across its contacts. This circuit extends from the line L2 across the contact of the switch 58, a coil 15 in the timing mechanism, to line L3. This energizes the coil and closes the auxiliary contacts 16 of a well known form of timing mechanism completing a circuit across a timing motor 11 to the line L3.

This sets the timing motor in operation which lafter a predetermined interval of time by means of a cam indicated at 11 closes the main contacts 1.8 of the timing mechanism. Before the main contacts 18 are closed the spring loaded pulling block 46 will have been moved farther f to the` right and after an additional als" movementthe clicker switch 51 opens and releases the forward operating coil 13 of the magnetic reversing switch causing the motor to stop.

The closing of the main contacts 18 of the timing mechanism completes a circuit for the reverse operating coil of the magnetic reversing switch. This circuit may be traced from the line L3 across the coil 80, the main contacts 18, the forward key 10, the reverse limit switch 6| which is now closed and the stop key 12 to the line L|. The reverse switch operating coil 80 operates and shifts its contact bar 8| closing a holding circuit for itself across the forward key 10. This closes the reverse operating circuit for the motor I8 causing the pulling blocks to be moved toward the clicker switch 58 open which released the coil 15 of the timing mechanism and stopped the operation of the timing mechanism.` All of the switches, etc. of Fig, 6 will now be in the positions indicated in Fig. 6.

Figs. 1, 2, 3 and 4 show the parts in the position they occupy as tension is applied to the cable. The wiring diagram in Fig. 6 shows the position of the switches when the machine is in its home position.

The motor may be stopped by pressing the stop key 12 which opens the holding circuits for the forward and reverse operating coils 13 and 80 of the magnetic reversing switch.

The motor may be operated in the reverse direction by pressingl the reverse key 1| which closes the operating circuit for the reverse operating coil 80 from the line L3, across the coil 80, reverse key 1|, forward key 10, reverse limit switch 6|, stop key 1.2 to line Ll The forward limit safety switch is provided to stop the motor in case the cable or fitting connection fails. The parts may then be returned to home position by pressing the reverse key 1|.

The mechanism illustrated and described constitutes a preferred embodiment of our. invention. It is obvious of course, that various changes may be made. The machine may be constructed to test cables of the same length and diameter and having similar end fittings. Itis preferred however to provide a machine which is long enough to test the longest of a series of vcables of different diameters, to adjustably mount the motor pulling block 33 to accommodate diffor opening the circuit of said motor upon a predetermined amount of movement of said first mentioned block, a timing mechanism, means also controlled vby said first mentioned block for setf, ting said timing mechanism in operation after a predetermined amount of movement of said first mentioned block and before the circuit of said operating motor has been opened, and means operable under control of said timing mechanism for closing a reverse circuit across saidoperatingmotor for returning said pulling blocks into their normal home positions to release said end fittings from said blocks.

5. In a machine of the class described, the combination of a resiliently loaded pulling block adapted to detachably receive an end fitting on a cable, a motor pullingv block adapted to detachably receive the other endl fitting on the cable and mounted for sliding movement toward and away from said first mentioned block, an elec- `tric* motor for operating said last mentioned block, switch means controlled by said first mentioned `block for opening the circuit of said operating motor upon a predetermined amount of movement of said first mentioned block, a timing mechanism, means also controlled by said rst mentioned block for setting said timing mechanism in'operation after a predetermined amount of movement of said rst mentioned block and before the circuit of the main operating motor has been opened, means operable under control of said timing mechanism for closing a reverse circuit across said operating motor for returning said4 pulling blocks into their normal home positions to release said end fittings from said blocks, means for automatically reversing the circuits across said operating motor` upon failureof the connection between an end tting and the cable and means for automatically opening the circuit of said operating motor for stopping said motor upon movement of said second mentioned block into its home position.

6. In a testing machine, the combination'of a spring loaded pulling block, a motor operated pulling block, means on said blocks facilitating attachment thereto of the ends of an elongated member, manual means for setting the motor in forward operation to move said motor operated pulling block in a direction away` from said spring loaded pulling block and through the elongated member move said spring loaded pulling block, means controlled by said spring loaded pulling block to stop the forward operation of said motor after a predetermined'increase of load'has been applied on said spring loaded pulling block and. after a predetermined'interval of time, to reverse the operation of said motor to restore the pulling blocks to their home positions.

7. A spring loaded blockl comprising a plate, a plunger slidalbly extending through said plate provided at oneend with a coupling Iblock to detachably receive one end of an elongated member to be tested and provided at its other end with a spring abutment, a spring between said abuting om movement of said block away from said plate.

8. In an apparatus of the character descrilbed block, means for connecting an article to be.

comprising a frame, a pulling block, Va reversible electric motor for operating said block, aloaded block, means for connecting an article tdrbe rtested to said blocks, a time delay mechanism for starting the reverse operation Yof said motor, and a pair of switches on said Alatter block including a normally open switchadapted -upon a predetermined forward -movement of said latter block to set said timing mechanism in operation and including a normally closed switch adapted upon a predetermined forward movement of said latter block to stop the forward operationfof said motor. y n c 9. In an apparatus of the .e character described comprising a frame, a pulling block, a reversible electric motor for operating said Iblock,v a loaded tested to said blocks, a circuit controlled time delay mechanism for starting the reverse operation of said motor, a pair of switches on said latter block including a normally open switch in i the circuit of said timing mechanism adapted upon forward movementV of said latter blockv to close the circuit of said timing mechanism-and including a normally closed switch adapted upon movement of said latter block to open the forward circuit of said-motor, the closing and open,- ing of said respective switches being timed so that said first mentioned switch will close a short interval of time before the'fsecond` mentioned switch opens. y.

10. In an apparatus of the character described comprising a frame, a pulling block, a reversible electric motor for operating said block, a loaded block, means for connecting an article to be tested to said blocks, av circuit `controlled time delay mechanism for starting the reverse operation of said motor, a pair of switches on said latv ter lblock including a normally open switch in ..40 the circuit of said timing mechanism adapted 11. Ina testing machine, the combinationv of means for tensioning .an article to be tested, manipulative means for setting said tensioning means in operation to tension said article, means set in operation by said article as a predetermined tension therein is attained for arresting the operation of said tensioning means, and delayed action means also set in operation by said article as its tension approaches the value of said predetermined tension for reversing the operation of said tensioning meansV after a predetermined lapse of time following the arrest ofv the operationof said tensioning means.

12. Ink a testingmachine, the. combination .of means forv tensioning an article to be tested,V manipulative means fortsetting said tensioning means in operation to tension said article, means automaticallyset in operation to arrest the operation of said tensioning means as a predetermined tension in the article is attained, and means also automatically set in operation to'reverse the operation of said tensioning means afterr a predetermined lapse of Itime following the arrest of said tensioning means.l

13. In a testing machine, the combination of e means for tensioning an article to be tested, comf prising4 means for applying tension to one end of said article and yielding means to resist movement of the other end of said article as said article is tensioned, means operated |by said yield- `ing means as a predetermined tension in the ar- Y ticle is attainedfor arresting said tension apply- 5 arrest of said tension applying means.

OTTO J. BRATZ. HARRY D. BALUSS.` 

